DOVER — The Senate will vote Thursday on the fourth bill in six years aimed at legalizing marijuana for medicinal purposes.

And the prime sponsor of HB 573, Rep. Donna Schlachman, D-Exeter, feels like this time it has a fighting chance.

The bill passed the full House at the end of March by a wide margin, and included a self-grow provision that would allow patients to cultivate marijuana in their homes for medical purposes.

However, because Gov. Maggie Hassan opposes the self-grow provision, the Senate Health, Education and Human Services Committee approved the bill with an amendment that removed the self-grow language, among other changes.

If the Senate passes HB 573 as amended on Thursday, the two houses will meet in a Committee of Conference to attempt a compromise on the bill’s final language before it lands on Gov. Hassan’s desk.

Schlachman said as the House’s position was to allow the self-grow provision, they are hoping to reach amendable language on the issue.

“We’re continuing to have dialogue with the Governor’s office, trying to find a level of comfort that would allow patients the ability to self grow while the dispensaries would get up and running,” Schlachman said, adding it would be about two years before the dispensaries would open.

She said she doesn’t anticipate the bill will be held up because of the issue.

One of the bill’s strengths, she said, is that it creates an advisory council comprised of legislators, medical and health officials, the Attorney General and members of the public and NH Civil Liberties Union, among other members.

The advisory council’s purpose would be to collect information that includes research studies on the health effects of cannabis for patients, the effectiveness of the state’s therapeutic cannabis program and of alternative treatment centers, and any illegal distribution of the drug to nonpatients.

Creation of the advisory council addresses a research and study component of legalizing marijuana for medicinal purposes that clinicians and law enforcement were hoping would be stronger in the bill.

Both groups jointly proposed an amendment during the hearing process on the bill that would have required study of the health impact of making marijuana available to patients on a statewide basis.

While the Senate committee rejected the idea, Dr. Seddon Savage of the American Medical Society said proponents of the amendment were simply trying to tighten the bill to make sure only people who have a “real and demonstrated need” have access to therapeutic cannabis.

“Our recommendation was that this is really experimental therapy,” said Savage. “Marijuana has been studied, and there’s no question it can be used for therapeutic benefit. But it’s not a medication and it’s not subject to the drug safety system we have in this country.”

However, Schlachman said a study can always be done and doesn’t need to be written into law.

“The problem has been getting the federal government to allow cannabis to be available for any researchers to actually do the research,” she said.

Savage noted that while marijuana has been studied and used for centuries to help with pain, weight-loss, nausea and poor appetite, among other health issues, it can have different effects and cause different results based on the patient.

“It’s important that we understand what we want and we need the (Food and Drug Administration) to say, ‘This is safe and this is unsafe,’” Savage said. “If we make marijuana available to anyone who wants it for every ache and pain, there will likely be people who benefit, but also people who are harmed. We just want to gather information.”

She said the nearly 20 states in which medical marijuana has been made legal aren’t doing studies as to whether a patient has been in a motor vehicle accident, experienced rapid heart rate or other symptoms as a result of using the drug for medicinal purposes.

“We need to collect patient-based data,” she said. “There are about 75 different cannabinoids in marijuana. They bind to different receptors and do different things. It can have benefits and risks.”

The New Hampshire Police Chiefs Association has consistently opposed legalization of medical marijuana for many reasons, but Enfield Police Chief and Vice President of the Association Richard Crate said they favored some kind of study if the measure were going to pass.

“We encouraged the Senate, as well as the governor, to look at study as a way to make it (medical marijuana) available for patients while studying the effects and to have the research that would support or may not support the claims that have been made in Concord over the years,” Crate said. “And it would best serve the patients because they would understand they’re going through a clinical study, and they would see where they benefit.”

Since the proposed amendment was shot down in committee, Crate said police officials have been making the Senate and Governor Hassan aware of other issues they have with the bill, such as the self-grow provision.

“We’re very concerned about that part of the bill because we feel that would be very difficult for law enforcement to be able to identify what’s being used for the medical portion and what’s being used recreationally,” he said.

“I don’t think we should be legalizing medicine,” Crate continued. “Marijuana has not been studied like other medications, and until it goes through those studies like any other medicine and is approved by the FDA, we’re circumventing the best practices. I think that’s why a lot of doctors and physicians have come out in opposition to this.”

But Schlachman maintains it doesn’t need further study, and the advisory council will collect data on diseases and what’s working.

“I don’t think we need to study the effects of it,” she said. “I think we have ample information that indicates it has significant positive impacts on certain people with certain diseases and illnesses. We’re trying to provide physicians with the opportunity to prescribe therapeutic cannabis.”